(数组)最长的连续元素序列长度

/**
  * 
  * @param num int整型一维数组 
  * @return int整型
  */
function longestConsecutive( num ) {
    // write code here
    var set = new Set(num);
    var max = 1;
    for(var i=0;i<num.length;i++){
        if(set.delete(num[i])){
            var large_val = num[i]+1;
            var small_val = num[i]-1;
            var count = 1;
            while(set.delete(large_val)){
                count++;
                large_val++;
            }
            while(set.delete(small_val)){
                count++;
                small_val--;
            }
            max = Math.max(max,count)
        }
    }
    return max;
}
module.exports = {
    longestConsecutive : longestConsecutive
};